The present invention relates to a connectorized substrate and method of connectorizing substrate and, in particular, a substrate having conductive areas and conductive spheres attached to the conductive areas in order to provide for electrical connection of the substrate to a motherboard.
The use of conductive spheres is known in the art for providing high density leads. For example, ball grid array packages are known for attaching the die of an integrated circuit to a printed circuit board. Such BGA packages are common having two-hundred and fifty-six balls on 0.050 inch.times.0.050 grids using 0.031/0.039 inch ball diameters, such as Jedec MO-156. However, such packages have been limited in their use for carrying IC or chips in order to accommodate the high density requirements.
Many substrates have conductive pads on their surfaces in order to allow for the quick attachment of the substrate to a motherboard. Such attachment is via surface mount (SMT) technology, where the conductive pad is oriented above a predetermined conductive area on the motherboard. Upon positioning of the substrate over the motherboard and reflow of the solder pad, an electrical connection may be made. Such conductive pads do not assimilate the contraction or expansion of the substrate and the motherboard due to temperature variations due to the different coefficient of expansion of the various substrates. In addition, traditional surface mount techniques do not provide an offset between the substrate and the motherboard in order to allow for inspection of the electrical connection or washing of the substrates.
Therefore, it is an object of the present invention to provide a connectorized substrate which provides for the quick and easy attachment of a substrate to a motherboard and provides for the assimilation of the different rates of expansion of the substrate materials and provides for an offset between the substrate and the motherboard.
It is another object of the present invention to provide for a substrate which may be quickly and easily attached to a motherboard.
It is a further object of the present invention to provide a method of making electrical connections between a substrate and a motherboard which assimilates the expansion differences of the substrate materials and provides for an offset between the substrate and the motherboard.
It is another object of the present invention to provide for a method of connectorizing a substrate wherein multiple electrical connectors may be mounted to a substrate quickly and inexpensively.